Rotationally stabilized contact lens

ABSTRACT

The stabilized contact lens methods and apparatus disclosed herein provide improved stabilization of a contact lens placed on a cornea of an eye. The contact lens comprises stabilization zones that allow the lens to repeatedly and consistently orient on the cornea such that a sensing zone located on the lower portion of the lens is located inferiorly to engage the lower eyelid. The stabilized contact lens can provide a lower pressure sensing zone with decreased thickness for pressure or other sensing related to the lower eyelid. The decreased thickness has the advantage of improving coupling between forces from an eyelid and a lower chamber of a fluidic module. The improved coupling allows increased amounts of fluid to move between the lower chamber and an upper optical chamber coupled to the lower chamber, such that the upper chamber can increase curvature and optical power in response to pressures of the eyelid.

CROSS-REFERENCE

This application is a continuation of U.S. patent application Ser. No.15/973,972, filed May 8, 2018, which is a continuation of InternationalApplication No. PCT/US2016/061697, filed Nov. 11, 2016, entitled“ROTATIONALLY STABILIZED CONTACT LENS”, which claims the benefit of U.S.Provisional Application No. 62/255,242, filed Nov. 13, 2015, entitled“ROTATIONALLY STABILIZED CONTACT LENS”, and U.S. Provisional ApplicationNo. 62/254,080, filed Nov. 11, 2015, entitled “ROTATIONALLY STABILIZEDCONTACT LENS”, which applications are incorporated herein by reference.

The subject matter of the present application is related to thefollowing international patent applications: PCT/US2014/013427, filed onJan. 28, 2014, entitled “Accommodating Soft Contact Lens”;PCT/US2014/013859, filed on Jan. 30, 2014, entitled “ManufacturingProcess of an Accommodating Contact Lens”; PCT/US2014/071988, filed onDec. 22, 2014, entitled “Fluidic Module For Accommodating Soft ContactLens”; U.S. Application Ser. No. 62/031,324, filed Jul. 31, 2014,entitled “Sacrificial Molding Process for an Accommodating ContactLens”; PCT/US2015/0433307, filed 31 Jul. 2015, entitled “LOWER LIDACTIVATING AN ELECTRONIC LENS”; PCT/US2016/061696, filed Nov. 11, 2016,entitled “SOFT CONTACT LENS MATERIAL WITH LOW VOLUMETRIC EXPANSION UPONHYDRATION”; and PCT/US2016/061700, filed Nov. 11, 2016, entitled“ACCOMMODATING LENS WITH CAVITY”; the entire disclosures of which areincorporated herein by reference.

The subject matter of the present application is also related to thefollowing provisional patent applications filed on Nov. 11, 2015: U.S.Provisional Application No. 62/254,048, entitled “SOFT CONTACT LENSMATERIAL WITH LOW VOLUMETRIC EXPANSION UPON HYDRATION”; U.S. ProvisionalApplication No. 62/254,080, entitled “ROTATIONALLY STABILIZED CONTACTLENS”; and U.S. Provisional Application No. 62/254,093, entitled“ACCOMMODATING LENS WITH CAVITY”, the entire disclosures of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

As the eye ages, the ability to accommodate or increase in power fornear vision deteriorates. By age 40, and on average by age 45, manypeople need some type of vision correction to see near objects.

Prior methods and apparatus for restoring accommodation are can be lessthan ideal in some respects. Although accommodating contact lenses havebeen proposed, at least some of these contact lenses have less thanideal alignment on the eye. With fluidic accommodating soft contactlenses, the eyelid can urge fluid from a lower portion of the lens to acentral portion to increase curvature of the central portion for nearvision.

Soft contact lenses normally rotate freely on the eye so a method tostabilize the rotation of lens is needed for the correction ofastigmatism. Although stabilized contact lenses have been proposed forvision correction of astigmatism, these prior approaches forstabilization are less than ideally suited for use with accommodatingcontact lenses. These lenses are commonly called soft toric contactlenses. A method to rotationally stabilize commercial soft contactlenses to correct astigmatism is to use thin and thick zones, thevariations in lens thickness, to interact with the eyelids. The earlydesigns using asymmetrical thickness were created using a simple tiltbetween the front and back surface of the soft contact lens. This tiltbeing the same as an optical prism, with a thin top and thick bottom,and the term “prism ballast” has been used to describe these lenses.While the thicker ‘bottom’ is heavier than the thinner ‘top’ of the lensthe lenses have been shown to orient independent of gravity anddependent upon the force of the upper eyelid upon blinking. Thisorientation independent of gravity can be described “as the watermelonseed principle”. Contemporary literature may still use the term “prismballast”, however, because of historical reference or because weight andgravity are a simpler concept than eyelid blink motions, pressure,compression and frictional forces. Prism can result in different amountsof thickness of lens material over an optical chamber within an opticalzone of an accommodating contact lens, which may result in distortion ofthe central region when fluid is passed to the chamber in order tocurvature of the central region.

In light of the above, improved accommodating contact lenses are neededwith improved stabilization.

SUMMARY OF THE INVENTION

The stabilized contact lens methods and apparatus disclosed hereinprovide improved stabilization of a contact lens placed on a cornea ofan eye. The contact lens comprises stabilization zones that allow thelens to repeatedly and consistently orient on the cornea such that asensing zone located on the lower portion of the lens is locatedinferiorly to engage the lower eyelid. Although specific reference ismade to an accommodating contact lens with a fluidic module, theembodiments disclosed herein can be used with any contact lens wherestabilization is helpful. The stabilized contact lens can provide alower pressure sensing zone with decreased thickness for pressure orother sensing related to the lower eyelid. The decreased thickness hasthe advantage of improving coupling between forces from an eyelid and alower chamber of a fluidic module. The improved coupling allowsincreased amounts of fluid to move between the lower chamber and anupper optical chamber coupled to the lower chamber, such that the upperchamber can increase curvature and optical power in response topressures of the eyelid. The improved stabilization helps to maintainthe lower chamber toward the lower eyelid. The improved stabilizationcan be provided with an upper stabilization zone and a zone of increasedthickness having increased thickness relative to the upper stabilizationzone. The pressure sensing zone can be located over the lower chamberwith decreased thickness relative to the zone of increased thickness toimprove coupling of the pressure sensing zone to the lower eyelid. Thestabilization provided with the upper stabilization zone and the zone ofincreased thickness can be sufficient to stabilize the lens with thedecreased mass of the sensing zone. Each of the upper stabilizationzone, the zone of increased thickness, and the pressure sensing zone maycomprise fillets defining boundaries of the corresponding zones. Thefillet boundaries can be arranged to provide stabilization, and maycomprise portions of the stabilization zones. The central optical zonecan be configured with decreased amounts of prism to improveaccommodative response, and the amount of prism can be less than 0.4 D.The zone of increased thickness may extend substantially around theoptical zone and comprise a zone of maximum thickness and a transitionzone. The transition zone may extend between the zone of maximumthickness and the optical zone in order to provide a smooth transitionfrom the zone of maximum thickness and the optical zone. The thickerportions of the transition zone adjacent the zone of maximum thicknessmay also contribute to stabilization of the lens. The transition zonemay extend to the boundary of the optical zone and have a decreasingthickness profile from the zone of maximum thickness to the opticalzone, such that a circular optical zone can be provided with decreasedamounts of prism.

In a first aspect, an accommodating contact lens for placement on an eyeis provided. The contact lens comprises an inner optical zone to providevariable optical power, an upper stabilization zone extending above theoptical zone between an upper boundary of the lens and the optical zone,a zone of increased thickness extending below the upper stabilizationzone, and a lower pressure sensitive zone coupled to the inner opticalzone to engage a lower eyelid and increase optical power of the inneroptical zone in response engagement with the lower eyelid. The zone ofincreased thickness comprises a thickness greater than the upperstabilization zone. The lower pressure sensitive zone comprises athickness less than the zone of increased thickness.

In many embodiments, the upper stabilization zone and the zone ofincreased thickness each may comprise a surface area greater than thepressure sensing zone in order to stabilize the lens.

In many embodiments, the upper stabilization zone may comprise acrescent shape. The zone of increased thickness may comprise an annularshape extending at least partially around the central optical zone. Thepressure sensitive zone may comprise a lentoid shape located between alower boundary of the lens and the optical zone.

In many embodiments, a lower boundary of the zone of increased thicknessmay comprise an indentation shaped to fit the lentoid shape of thepressure sensitive zone between the zone of increased thickness and thelower boundary of the lens.

In many embodiments, the upper stabilization zone may comprise athickness within a range from about 75 to 250 μm. The zone of increasedthickness may comprise a thickness within a range from about 300-500 μm.The pressure sensitive zone may comprise a thickness within a range fromabout 50 to 300 μm.

In many embodiments, a difference in thickness between the upperstabilization zone and the zone of increased thickness may be within arange from about 150 μm to about 300 μm. The upper stabilization zonemay comprise a surface area within a range from about 3 mm² to about 15mm². The zone of increased thickness may comprise an area within a rangefrom about 4 mm² to about 20 mm² having the difference in thicknesswithin the range from about 150 to 300 μm, The pressure sensitive zonemay comprise a surface area within a range from about 1 mm² to about 6mm².

In many embodiments, the optical zone may comprise a center of the lenslocated along a midline of the lens. The pressure sensitive zone may belocated along a midline of the lens corresponding to a 90 degree axis ofthe lens.

In many embodiments, the zone of increased thickness may comprise afirst portion located on a first side of the lens and a second portionon a second side of the lens. The pressure sensitive zone may be locatedat least partially between the first portion and the second portion. Thefirst portion and the second portion may comprise similar thicknessesgreater than the thickness of the pressure sensitive zone, such thatmass per unit area of the pressure sensitive zone is decreased relativeto mass of the first portion and the second portion per unit area. Theupper stabilization zone and the zone of increased thickness may bearranged to stabilize the contact lens upon engagement with a lowereyelid of the eye.

In many embodiments, the inner optical zone may comprise a centraloptical zone.

In many embodiments, the contact lens may further comprise a transitionzone extending around the optical zone.

In many embodiments, the optical zone may comprise an inner portion andan outer portion. At least the inner portion may be configured toincrease optical power in response to the lower eyelid engaging thepressure sensitive zone.

In many embodiments, the optical zone may comprise prism. The opticalzone may comprise prism of less than 0.5 D. The optical zone maycomprise prism of no more than one or more of 0.4 D, 0.3 D, 0.2 D or 0.1D.

In many embodiments, the optical zone may comprise one or more of afluidic chamber or liquid crystal

In many embodiments, the zone of increased thickness may comprise a zoneof maximum thickness and a transition zone. The transition zone mayextend between the zone of maximum thickness and the optical zone. Thetransition zone may have a thickness profile extending to a uniformthickness around the central optical zone in order to provide theoptical zone.

In many embodiments, the upper stabilization zone and zone of increasedthickness each may comprise prism. The zone of increased thickness maycomprise a zone of maximum thickness and a transition zone. Thetransition zone may extend between the zone of maximum thickness and theoptical zone. The transition zone may have a thickness profile extendingto a uniform thickness around the central optical zone in order toprovide the optical zone with a boundary having a substantially constantthickness.

In many embodiments, the optical zone may comprise an optical fluidicchamber configured to increase curvature in response to eyelid pressureon the pressure sensing region. The pressure sensing region may comprisea fluidic reservoir chamber coupled to the optical chamber with achannel extending there-between to pass fluid to the optical chamber inresponse to eyelid pressure.

In many embodiments, the optical zone may comprise liquid crystalmaterial between electrodes. The pressure sensing region may comprise apressure sensor coupled to the electrodes with a circuit to increaseoptical power of the liquid crystal material in response to eyelidpressure sensed with the pressure sensor.

In many embodiments, a plurality of fillets may extend around one ormore of the upper stabilization zone, the zone of increased thickness,the zone of maximum thickness, the transition zone, or the pressuresensing zone. For example, a plurality of fillets may extend around eachof the upper stabilization zone, the zone of increased thickness, thezone of maximum thickness, the transition zone, and the pressure sensingzone. Alternatively or in combination, the plurality of fillets maydefine one or more boundaries of the one or more of the upperstabilization zone, the zone of increased thickness, the zone of maximumthickness, the transition zone, or the pressure sensing zone. Theplurality of fillets may define boundaries of each of the upperstabilization zone, the zone of increased thickness, the zone of maximumthickness, the transition zone, or the pressure sensing zone.Alternatively or in combination, one or more of the upper stabilizationzone, the zone of increased thickness, the zone of maximum thickness,the transition zone, or the pressure sensing zone may comprise theplurality of fillets.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIG. 1 shows an accommodating contact lens, in accordance withembodiments;

FIG. 2 shows a stabilized contact lens, in accordance with embodiments;

FIG. 3A shows views of the stabilized contact lens of FIG. 2, inaccordance with embodiments;

FIG. 3B shows a side profile illustration of the stabilized contact lensof FIG. 3A;

FIG. 3C shows thickness at locations of the lens as in FIGS. 3A and 3B;

FIG. 4A shows a stabilized contact lens as in FIGS. 3A and 3B, inaccordance with embodiments;

FIG. 4B shows a horizontal cross-sectional profile and thicknesses ofthe stabilized contact lens of FIG. 4A, in accordance with embodiments;

FIG. 4C shows rounded structure on the edge of the contact lens as inFIG. 4A, in accordance with embodiments;

FIG. 4D shows a vertical cross-sectional profile and thicknesses of thestabilized contact lens of FIG. 4A, in accordance with embodiments;

FIG. 4E shows a vertical cross-sectional profile and thicknesses of thepressure sensing zone of the stabilized contact lens of FIG. 4A, inaccordance with embodiments;

FIG. 4F shows a vertical cross-sectional profile and thicknesses of theupper stabilization zone of the stabilized contact lens of FIG. 4A, inaccordance with embodiments;

FIG. 5 shows a stabilized lens, in accordance with embodiments; and

FIG. 6 shows an inlay comprising a module placed in a stabilized contactlens.

DETAILED DESCRIPTION OF THE INVENTION

The contact lens and related methods and apparatus are well suited formany types of contact lenses, such as accommodating soft contact lenses.Although specific reference is made to stabilized accommodating contactlenses with fluidic coupling, the stabilized contact lenses disclosedherein can be used with many types of contact lenses, rigid and softcontact lenses and accommodating contact lenses such as electroniccontact lenses, accommodating electronic contact lenses, other types ofaccommodating contact lenses response to engagement with a lower eyelid.The fluidic contact lens comprises an inner optical chamber configuredto increase optical power and a lower chamber fluidically coupled to theoptical chamber to increase optical power when the lower chamber engagesthe lower eyelid. The inner optical chamber and the lower chamber can becoupled to each other with a channel such as a microchannel.

As used herein the term “lower” refers to inferior on the subject whenthe contact lens is placed and the subject is standing.

As used herein the term “upper” refers to superior on the subject whenthe contact lens is placed and the subject is standing.

The desired action of the accommodating contact lens is to increasepower of the contact lens, for example, for reading by using the changein eye position of looking down to read.

Examples of accommodating contact lenses suitable for incorporation inaccordance with embodiments disclosed herein are described in thefollowing patent applications: PCT/US2014/071988, published asWO/2015/095891, entitled “FLUIDIC MODULE FOR ACCOMMODATING SOFT CONTACTLENS”, filed 25 Jun. 2015; PCT/US2014/013859, published asWO/2014/120928, entitled “MANUFACTURING PROCESS OF AN ACCOMMODATING SOFTCONTACT LENS”, filed 7 Aug. 2014; PCT/US2014/013427, published asWO/2014/117173, entitled “ACCOMMODATING SOFT CONTACT LENS”, filed 31Jul. 2014; PCT/US2015/0433307, filed 31 Jul. 2015, entitled “LOWER LIDACTIVATING AN ELECTRONIC LENS”; the entire disclosures of which areincorporated herein by reference.

FIG. 1 shows an accommodating contact lens in accordance withembodiments.

In many embodiments, the soft contact lens 100 comprises components: (1)the encapsulating soft lens material 110 and an optional accommodatingmodule 120. The accommodating module comprises two chambers connected bya channel 130. The outer lower chamber 140 takes the pressure of lowereyelid on the lens surface and converts it into chamber pressure thatincreases as the lower eyelid margin 150 rises (relative to the contactlens) from looking straight ahead (primary gaze) to looking down to read(down gaze position). The central optical chamber 160 increases theoptical power of the lens when inflated by an increase in chamberpressure. Although an accommodation module is shown, the two chambersand channel can be formed within the contact lens material without amodule, for example, by forming these structures in the soft contactlens material such that these structures are defined by the soft contactlens material.

The lens 100 comprises an optical zone 170 configured to providevariable optical power. Optical zone 170 may comprise one or more of afluidic chamber or liquid crystal. Optical zone 170 is configured toprovide far vision when the eyelid is away from the pressure sensitivezone. The optical zone 170 can be larger than the central opticalchamber 160, for example.

The central optical chamber 160 can be positioned in many ways inrelation to the contact lens in order to accommodate anatomicalvariability of the eye. For example, the central optical chamber 160 maybe positioned within the soft contact lens 100 away from a center of thecontact lens such that the central fluidic chamber 160 is concentricwith the pupil. Alternatively, the central optical chamber 160 can beconcentric with the contact lens 100. A person of ordinary skill in theart will recognize that the pupil may be located away from the center ofthe cornea and design the contact lens accordingly in accordance withthe embodiments disclosed herein. This approach allows the center of thecentral optical chamber 160 to be centered on the pupil when the softcontact lens 100 is placed on the eye. The central optical chamber 160may be concentric or eccentric within the soft contact lens 100, such aswith respect to the center of the soft contact lens 100. The softcontact lens 100 may configured such that the optical zone 170 isconcentric or eccentric with respect to the center of the soft contactlens 100. The soft contact lens 100 may be configured such that theoptical zone 170 is concentric or eccentric with respect to the pupil ofthe eye.

The diameter or maximum dimension across of the optical zone 170 and/orcentral optical chamber 160 may be sized to match the pupil based onphysiological norms. The diameter of the optical zone 170 or centraloptical chamber 160 may be within a range of about 2.5 mm to about 6 mm,for example within a range of about 3 mm to about 6 mm.

The desired accommodative action may be driven by the interactionbetween the lower chamber and lower eyelid. A method to maintain theorientation position of the lower chamber, within the soft contact lens,to be ‘down’ and in contact with the lower eye lid is also helpful.

The outer chamber 140 can be configured in many ways when connected tothe central chamber 160 in order to provide accommodation. In manyinstances, the upper lid may contribute to the accommodation of the softcontact lens 100 as well. The upper lid may engage one or more of thefluid chambers during down-gaze or squinting, thereby compressing thefluid chamber(s) and altering the shape of at least the central fluidicchamber 160 in order to alter the optical power as described herein. Theouter chamber 140 may be connected to the central chamber 160 and sizedand shaped in many ways, for example with an annular outer chamberextending around the central optical chamber. Alternatively or incombination, the upper lid may engage one or more outer upper fluidchambers disposed above the central fluidic chamber 160. The upper fluidchamber(s) may be coupled to the central fluidic chamber 160 by an upperchannel to allow fluid to flow between the upper fluid chamber(s) andthe central fluidic chamber 160. The contact lens 100 may comprise anycombination of a central fluidic chamber 160, an upper fluidic chamber,and a lower fluidic chamber 140. The contact lens 100 may, for example,comprise a central fluidic chamber 160 coupled to an upper fluidicchamber by an upper channel and a lower fluidic chamber 140 by a lowerfluid channel as described herein. The contact lens 100 mayalternatively comprise a central fluidic chamber 160 and one or moreupper fluid chambers without a lower fluidic chamber 140. Engagement ofthe upper fluid chamber(s) with the upper eyelid may function to adjustthe optical power of the contact lens 100 in a near vision configurationor far vision configuration in a manner substantially similar to that ofthe lower fluidic chamber(s) 140 described herein.

The accommodating soft contact lenses are well suited for the correctionof astigmatism, which is achieved by two optical powers at 90 degreesapart as described by a toric surface. Each power has an axis and apower meridian. By convention either the axis of the most plus power(called plus cylinder notation) or the most minus power (called minuscylinder notation) is used to described optical orientation relative tothe horizontal from zero to 179 degrees. The axis being symmetrical at180 degrees. The refractive astigmatism of the eye is corrected by softcontact lenses of equal and opposite ‘astigmatism’ or toricity at thesame axis. Soft contact lenses normally rotate freely on the eye sostructures to stabilize the rotation of lens is helpful for thecorrection of astigmatism with the accommodating contact lenses asdisclosed herein.

The rotationally stabilized soft contact lenses can use thick and thinzones, in which the variations in lens thickness interact with theeyelids to stabilize the lens. In some embodiments, asymmetricalthickness can be provided using a simple tilt between the front and backsurface of the soft contact lens. This tilt may comprise optical prism,with a thin top and thick bottom. The optical zone can be configuredwithout prism, such that the stabilizing zones with prism extend aroundthe optical zone. While the thicker ‘bottom’ is heavier than the thinner‘top’ of the lens the lenses are capable of orienting independent ofgravity and dependent upon the force of the upper eyelid upon blinking.The embodiments disclosed herein can rely on one or more of eyelid blinkmotions, pressure, compression or frictional forces. In manyembodiments, removed excess material from a lower pressure sensitivezone of the lens changes the center of gravity of the lens higher. Suchlenses would be less stable if gravity was the mechanism of action.Actual clinical testing, however, has shown excellent stabilizationcharacteristics supporting the thickness stabilization mechanism ofaction as disclosed herein. For the accommodating contact lens, athickness profile design with a definite top and bottom is preferable asthe lens has a single ‘top’ (away from the lower module) and ‘bottom’(with lower module).

While the rotationally stabilized lens can be configured in many ways,in many instances the lens will have one or more of the followingproperties:

1) Thin top increasing in thickness to a maximum thickness just belowthe midline of the lens. The optimal thickness at the top of the lens is0.100 mm, and 0.350 mm at the maximum, for a differential of at leastabout 0.200 mm, for example.

2) A substantially ‘prism free’ or uniform thickness across the opticalzone. For example, less than a 10% variation in thickness of theencapsulating contact lens can be provided in front of the opticallyused portion of the module. In many instances, the amount of prism is nomore than about 0.4 D.

3) A reduction in thickness over the center of the non-optically usedouter lower module chamber. The thickness of the lens material of thepressure sensing zone over the outer lower module can be in a range fromabout 0.025 mm to about 0.2 mm, for example within a range from about0.050 mm to about 0.0150 mm. An optimal thickness of 0.100 mm over thecenter of the outer/lower module chamber can be provided.

FIG. 2 shows structures of stabilized contact lens 100. Lens 100comprises an arrangement of structures to stabilize the lens. An upperstabilization zone 210 is generally located above the optical zone 170.Upper stabilization zone 210 comprises a crescent shape. A zone ofincreased thickness 220 is located below the upper stabilization zoneand extends substantially around the optical zone. Zone of increasedthickness 220 comprises a generally annular shape and extends around atleast about half of the optical zone. Zone of increased thickness 220comprises an upper boundary shaped to fit and correspond to the lowerboundary of the upper stabilization zone. The zone of increasedthickness 220 comprises a thickness greater than the upper stabilizationzone in order to stabilize the lens on the eye.

Lens 100 comprises a pressure sensitive zone 230 coupled to the opticalzone 170. Pressure sensitive zone 230 comprises a lentoid shape with athickness less than the zone of increased thickness 220, in order tocouple pressure from the eyelid to a pressure sensitive structure withinthe pressure sensitive zone. Pressure sensitive zone 230 is generallylocated between the lower boundary of the lens and the optical zone 170.The zone of increased thickness 220 comprises a lower boundary shaped tofit and correspond to the upper boundary of the pressure sensitive zone230. Lens 100 comprises a midline 240 extending through a center 250 andcorresponding to a 90 degree axis of the lens 100. The stabilizingstructures of the lens can be symmetrically disposed about the midline240.

Optical zone 170 may comprise a pressure sensor or lower chamber fluidicmodule coupled to the pressure sensing zone 230 as described inapplication PCT/US2014/071988, previously incorporated by referenceherein.

Optical zone 170 may comprise an optical fluidic chamber configured toincrease curvature in response to eyelid pressure on the pressuresensing zone 230. The pressure sensing zone 230 comprises a fluidicreservoir chamber coupled to the optical chamber with a channelextending there-between to pass fluid to the optical chamber in responseto eyelid pressure.

In an alternative embodiment, optical zone 170 may comprise a liquidcrystal material between electrodes with the pressure sensing zone 230comprising a pressure sensor coupled to the electrodes with a circuit toincrease optical power of the liquid crystal material in response toeyelid pressure sensed with the pressure sensor.

The optical zone 170 comprises a maximum dimension across, such as adiameter 180 of the optical zone. The lens 100 comprises a maximumdimension across, such as diameter 190. The optical zone can be sized inmany ways, and can be within a range from about 3 mm to about 9 mm, forexample within a range from about 5 mm to about 8 mm.

The upper stabilization zone 210 and zone of increased thickness 220 mayeach comprise a surface area greater than the pressure sensing zone inorder to stabilize the lens.

FIG. 3A shows views of the stabilized contact lens of FIG. 2. The upperstabilization zone 210 of lens 100 comprises a thinner section whichramps up in thickness from top to bottom. This provides the inclinedplane effect for the upper eyelid to orient the lens with zone ofgreater thickness down, away, from the eyelid during blinking. The upperstabilization zone comprises a thickness within a range from about 75 to250 μm. The zone of increased thickness 220 comprises a thicker sectionwith thickness within a range from about 300 to 500 μm (micrometers),for example. The difference in thickness between the upper stabilizationzone 210 and the zone of increased thickness can be in a range fromabout 150 to 300 μm, for example. The pressure sensitive zone 230comprises a thickness within a range from about 50 to 300 μm, forexample.

The upper stabilization zone 210 may comprise a surface area within arange from about 3 to 15 mm² and the zone of increased thickness 220 maycomprise a surface area within a range from about 3 to 20 mm², forexample. The pressure sensitive zone 230 may comprise a surface areawithin a range from about 1 to 6 mm².

FIG. 3B shows a side profile illustration of the stabilized contact lensof FIG. 3A.

FIG. 3C shows thickness at locations of a −1.00 Diopter lens as in FIGS.3A and 3B. The thickness of the upper stabilization zone 210 may beabout 150 μm, with the thickness of the lens tapering down to about 100μm at the upper lens edge 310. The fillet 320 at transition between thelower edge of the upper stabilization zone 210 and the upper edge of theoptical zone may have an increased thickness of about 235 μm. Thethickness of the central optical zone 170 may be about 225 μm until theouter edge 330, at which point the thickness increases to about 230 μm.The thickness of the central optical zone can vary in accordance withthe refractive correction of the lens, and may comprise an anteriortoric surface, for example. The zone of increased thickness 220 may havea thickness of about 300 um, which may increase to about 420 μm in thefillet 370 at the transition between the outer edge of the zone ofincreased thickness 220 and the surrounding outer lens 380, which mayhave a thickness of about 225 μm and taper down to about 115 μm at theouter edge 390 of the lens 100, for example. The pressure sensitive zone230 may have a center 235 having a thickness of 265 μm, with a thinnerupper edge fillet 340 having a thickness of about 250 μm at thetransition to the zone of increased thickness or optical zone (dependingon the configuration), and thicker at lower edge fillet 350 at about 300μm where the pressure sensitive zone 230 transitions into thesurrounding outer lens 380. The pressure sensitive zone is locatedbetween fillet 340 and fillet 350, which may comprise a decreasedthickness between the upper fillet and the lower fillet. The lower lensedge 360 further tapers down to about 105 μm.

The optical zone 170 may comprise prism of less than 0.5 D. Preferably,the optical zone 170 comprises prism of no more than one or more of 0.4D, 0.3 D, 0.2 D, or 0.1 D. The optical zone can be sized in many waysand comprises a maximum dimension across, such as a diameter, within arange from about 4 to 8 mm, for example.

Alternatively, the optical zone may comprise at least some prism.

The zone of increased thickness 220 may extend substantially around theoptical zone and comprise a transition zone 227 and a zone of maximumthickness 223. The zone of maximum thickness 223 comprises a thicknesswithin a range having values that are greater than other regions of thelens. The zone of maximum thickness 223 may comprise an annular zoneextending at least partially around the optical zone, and may besymmetrically disposed about a midline of the lens extending through theoptical zone of the lens and pressure sensing portion of the lens. Thezone of maximum thickness may comprise one or more fillets in order toprovide a smooth surface for the eyelid to slide over this zone. Thetransition zone extends between the zone of maximum thickness andoptical zone and may comprise a thickness profile extending from thezone of maximum thickness to a uniform thickness around the outerboundary of the central optical zone 170.

The upper stabilization zone 210 and zone of increased thickness 230 mayeach comprise prism, wherein the zone of increased thickness 220 extendsaround the optical zone 170 and comprises a transition zone having ashape profile extending to a uniform thickness around the centraloptical zone 170 in order to provide the optical zone 170 with aboundary having a substantially constant thickness and circular profilefor lenses with spherical correction. The transition zone may have avarying thickness around the central optical zone in order toaccommodate non-spherical shapes of the central optical zone, such astoric or wavefront and other corrective shapes.

The optical prism of the upper stabilization zone and the zone ofincreased thickness can be configured in many ways, for example withcenter of curvature located off axis away from a center of curvature ofthe back radius of curvature, for example.

In many embodiments, the upper stabilization zone comprises the filletsas described herein, which define a boundary of the upper stabilizationzone. The zone of increased thickness may also comprise fillets asdescribed herein, which define a boundary of the zone of increasedthickness. The pressure sensing zone may also comprise fillets asdescribed herein and be bounded by fillets, which define a boundary ofthe pressure sensitive zone. The zone of increased thickness andpressure sensing zone may comprise a common fillet shaped to fit thepressure sensing zone beneath the zone of increased thickness.

The zone of increased thickness can be configured in many ways and maycomprise the fillets that define its boundary, and also a transitionzone extending within the zone of increased thickness to the opticalzone in order to provide a substantially uniform thickness around theouter boundary of the optical zone. The substantially uniform thicknessaround the outer boundary of the optical zone can allow a sphericaloptical zone to have a circular diameter. With the optical zone shapedto define toric lenses, the transition zone can be shaped with a varyingthickness profile around a circular optical zone in order to provide acircular diameter to the toric optical zone.

FIG. 4A shows a stabilized contact lens 100 as in FIGS. 3A and 3B.

FIG. 4B shows a horizontal cross-sectional profile and thicknesses ofthe stabilized contact lens of FIG. 4A. The center of the optical zone170 may have a thickness of 225 μm, with an outer edge 330 having athickness of around 235 μm, for example. Embodiments may include atransition zone 400 extending around outer edge 330 of the optical zone170 from the optical zone to the zone of increased thickness 220. Theouter edge 410 of the transition zone 400 may have a thickness of 290μm, for example.

The optical zone may comprise an inner and an outer portion with atleast the inner portion configured to increase optical power in responseto the lower eyelid engaging the pressure sensitive zone 230 asdescribed herein.

From the outer edge 410 of the transition zone 400, the thickness of thelens increases within the zone of increased thickness 220, reaching amaximal thickness of about 420 μm at fillet 370 between zone ofincreased thickness 220 and surrounding outer lens 380. The surroundingouter lens 380 has a taper and decreased thickness compared to fillet370, for example 255 μm.

FIG. 4C shows rounded structures on the edge of the contact lens as inFIG. 4A. Continuing outward from the structure shown in FIG. 4B, thesurrounding outer lens 380 may decrease until it reaches a finalthickness of 115 μm at the rounded or beveled structures 420 of theouter lens edge 390.

FIG. 4D shows a vertical cross-sectional profile and thicknesses of thestabilized contact lens of FIG. 4A.

The upper stabilization zone 210 may have a central thickness of 175 μmwith its upper edge thickness decreasing to 140 μm. The optical zone 170may have a central thickness of 225 μm and a slightly higher thicknessat its outer edges 330, for example, which can vary with the curvatureof the lens. Below the optical zone 170, the lower edge 440 of fillet340 may comprise a thickness of about 235 μm at the transition into thepressure sensitive zone 230. The thickness of the pressure sensitivezone may increase between lower edge 440 and a center 235 of thepressure sensitive zone, and increase further until it reaches a maximalthickness of about 300 μm at the edge 450 of boundary fillet 350positioned at the transition between the pressure sensitive zone 230 andsurrounding outer lens 380. The increased thickness of the lower edge450 of the pressure sensing portion relative to the thickness of thecenter of the pressure sensing zone can provide improved stability andimproved pressure sensing.

FIG. 4E shows a vertical cross-sectional profile and thicknesses of thepressure sensing zone of the stabilized contact lens of FIGS. 4A and 4D.

Continuing past fillet edge 450, the surrounding outer lens 380decreases in thickness, in this instance to about 205 μm, beforetapering down further at the lower lens edge 360 to a final thickness ofabout 115 μm.

FIG. 4F shows a vertical cross-sectional profile and thicknesses of theupper stabilization zone of the stabilized contact lens of FIG. 4A.

The upper edge 430 of the upper stabilization zone 210 may decrease to athickness of about 140 μm. Continuing past the upper stabilization zone210, lens thickness may further decrease towards the upper lens edge310, reaching a final thickness of about 115 μm.

FIG. 5 shows stabilized lens 100, which may comprise an optical zone asdescribed herein.

The lower stabilizing zone 220 may comprise a first portion 530 locatedon a first side of the lens midline 240 and a second portion 540 on asecond side of the lens midline. The pressure sensitive zone 230 islocated at least partially between the first portion 530 and secondportion 540. The first portion 530 may comprise a first fillet 535, andthe second portion 540 may comprise a second fillet 545. The upperstabilization zone 210 and the zone of increased thickness 220 arearranged to stabilize the contact lens upon engagement with a lowereyelid of the eye as described herein.

The first portion 530 and second portion 540 comprise similarthicknesses which are greater than the thickness of the pressuresensitive zone 230 in order that the mass per unit area of the pressuresensitive zone is decreased relative to the mass per unit area of thetwo portions. The contact lens described with reference to FIGS. 2-4Fcan be similarly configured.

The first portion 530 and second portion 540 each comprise a surfacearea of at least about 1 mm². The pressure sensitive zone 230 comprisesa surface area of at least about 0.1 mm². The contact lens describedwith reference to FIGS. 2-4F can be similarly configured.

The thick sections of the first portion 530 and second portion 540 aresymmetrical with respect to the midline 240. An upwardly subtendingangle alpha 510 may be between within a range from about 10 to about 40degrees off the horizontal axis. A downwardly subtending angle beta 520may be within a range from about 20 to about 75 degrees off thehorizontal access.

FIG. 6 shows an inlay placed in a stabilized contact lens. The inlay maycomprise an inlay of an accommodating module or electronic circuit, or acombination thereof, for example. The inlay can be positioned at adistance within a range from about 25 μm to about 100 μm, for exampleabout 50 μm, from a back surface of the contact lens. The back surfaceof the contact lens has a back radius of curvature BCR. Alternatively,the module could be positioned at a distance within a range from about25 to about 100 μm from the front surface of the lens.

Although reference is made to soft contact lenses comprising a module,accommodating contact lenses can be configured without a module, inwhich the soft contact lens comprises the central optical chamber andthe outer lower chamber with the channel in between. Each of thesestructures may comprise cavities formed in the contact lens, in whichthe interconnected cavities contain a fluid with an index of refractiongreater than the contact lens material.

Examples of modules and sensors suitable for incorporation with thestabilized contact lens as disclosed herein are described inPCT/US2014/013427, filed on 28 Jan. 2014, entitled “Accommodating SoftContact Lens” (attorney docket no. 44910-703.601); PCT/US2014/013859,filed on Jan. 30, 2014, entitled “Manufacturing Process of anAccommodating Contact Lens” (attorney docket no. 44910-704.601);PCT/US2014/071988, filed on Dec. 22, 2014, entitled “Fluidic Module ForAccommodating Soft Contact Lens” (attorney docket no. 44910-705.601);and PCT/US2015/0433307, filed 31 Jul. 2015, entitled “LOWER LIDACTIVATING AN ELECTRONIC LENS”; the entire disclosures of which havebeen previously incorporated herein by reference. For example, the lensmay comprise a self-supporting electronics module comprising circuitryembedded in the hydrogel material of the stabilized contact lens asdisclosed herein.

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the invention. It should be understoodthat various alternatives to the embodiments of the invention describedherein may be employed in practicing the invention. It is intended thatthe following claims define the scope of the invention and that methodsand structures within the scope of these claims and their equivalents becovered thereby.

1. An accommodating contact lens for placement on an eye, comprising: aninner optical zone to provide variable optical power; an upperstabilization zone extending above the optical zone between an upperboundary of the lens and the optical zone; a zone of increased thicknessextending below the upper stabilization zone, the zone of increasedthickness comprising a thickness greater than the upper stabilizationzone; and a lower pressure sensitive zone coupled to the inner opticalzone to engage a lower eyelid and increase optical power of the inneroptical zone in response engagement with the lower eyelid, wherein thelower pressure sensitive zone comprises a thickness less than the zoneof increased thickness.
 2. The contact lens of claim 1, wherein theupper stabilization zone and the zone of increased thickness eachcomprise a surface area greater than the pressure sensing zone in orderto stabilize the lens.
 3. The contact lens of claim 1, wherein the upperstabilization zone comprises a crescent shape, the zone of increasedthickness comprising an annular shape extending at least partiallyaround the central optical zone, the pressure sensitive zone comprisinga lentoid shape located between a lower boundary of the lens and theoptical zone.
 4. The contact lens of claim 1, wherein a lower boundaryof the zone of increased thickness comprises an indentation shaped tofit the lentoid shape of the pressure sensitive zone between the zone ofincreased thickness and the lower boundary of the lens.
 5. The contactlens of claim 1, wherein the upper stabilization zone comprises athickness within a range from about 75 to 250 μm, and the zone ofincreased thickness comprises a thickness within a range from about300-500 μm and the pressure sensitive zone comprises a thickness withina range from about 50 to 300 μm.
 6. The contact lens of claim 1, whereina difference in thickness between the upper stabilization zone and thezone of increased thickness is within a range from about 150 μm to about300 μm and wherein the upper stabilization zone comprises a surface areawithin a range from about 3 mm2 to about 15 mm2 and the zone ofincreased thickness comprises an area within a range from about 4 mm2 toabout 20 mm2 having the difference in thickness within the range fromabout 150 to 300 μm and wherein the pressure sensitive zone comprises asurface area within a range from about 1 mm2 to about 6 mm2.
 7. Thecontact lens of claim 1, wherein the optical zone comprises a center ofthe lens located along a midline of the lens and wherein the pressuresensitive zone is located along a midline of the lens corresponding to a90 degree axis of the lens.
 8. The contact lens of claim 1, wherein thezone of increased thickness comprises a first portion located on a firstside of the lens and a second portion on a second side of the lens andwherein the pressure sensitive zone is located at least partiallybetween the first portion and the second portion.
 9. The contact lens ofclaim 8, wherein the first portion and a second portion comprise similarthicknesses greater than the thickness of the pressure sensitive zone,such that mass per unit area of the pressure sensitive zone is decreasedrelative to mass of the first portion and the second portion per unitarea and wherein the upper stabilization zone and the zone of increasedthickness are arranged to stabilize the contact lens upon engagementwith a lower eyelid of the eye.
 10. The contact lens of claim 1, whereinthe inner optical zone comprises a central optical zone.
 11. The contactlens of claim 1, further comprising a transition zone extending aroundthe optical zone.
 12. The contact lens of claim 1, wherein the opticalzone comprises an inner portion and an outer portion, at least the innerportion configured to increase optical power in response to the lowereyelid engaging the pressure sensitive zone.
 13. The contact lens ofclaim 1, wherein the optical zone comprises prism of less than 0.5 D.14. The contact lens of claim 1, wherein the optical zone comprisesprism of no more than one or more of 0.4 D, 0.3 D, 0.2 D or 0.1 D. 15.The contact lens of claim 1, wherein the optical zone comprises prism.16. The contact lens of claim 1, wherein the optical zone comprises oneor more of a fluidic chamber or liquid crystal.
 17. The contact lens ofclaim 1, wherein the zone of increased thickness comprises a zone ofmaximum thickness and a transition zone, wherein the transition zoneextends between the zone of maximum thickness and the optical zone, thetransition zone having a thickness profile extending to a uniformthickness around the central optical zone in order to provide theoptical zone.
 18. The contact lens of claim 1, wherein the upperstabilization zone and zone of increased thickness each comprise prismand wherein the zone of increased thickness comprises a zone of maximumthickness and a transition zone, the transition zone extending betweenthe zone of maximum thickness and the optical zone, the transition zonehaving a thickness profile extending to a uniform thickness around thecentral optical zone in order to provide the optical zone with aboundary having a substantially constant thickness.
 19. The contact lensof claim 1, wherein the optical zone comprises an optical fluidicchamber configured to increase curvature in response to eyelid pressureon the pressure sensing region and wherein the pressure sensing regioncomprises a fluidic reservoir chamber coupled to the optical chamberwith a channel extending there-between to pass fluid to the opticalchamber in response to eyelid pressure.
 20. The contact lens of claim 1,wherein the optical zone comprises liquid crystal material betweenelectrodes and the pressure sensing region comprises a pressure sensorcoupled to the electrodes with a circuit to increase optical power ofthe liquid crystal material in response to eyelid pressure sensed withthe pressure sensor. 21.-25. (canceled)